The wire drawing die core is the core component of the diamond wire drawing die. According to the material, it can be divided into three categories: PCD (polycrystalline diamond) core, CVD diamond core and single crystal diamond core. Therefore, the wire drawing die containing PCD core is called For PCD drawing dies.
How many types of wire drawing die cores are there?
Common wire drawing die core models on the market include three series: SD, CXD and CXT.
- PCD mold core: The successful development of PCD has brought great changes to the wire drawing industry, which makes the entire processing process more efficient and stable. PCD is made by sintering micron-sized diamond particles and binder under high temperature and high pressure conditions. It has the advantages of high hardness, good wear resistance, and strong impact resistance. The mold uses the advantages of uniform wear and long life. It is suitable for High-speed drawing. Because PCD is macroscopically isotropic, it will not have uneven die hole wear and out-of-round die hole like single crystal diamond. In addition, because the price of PCD is much lower than that of single crystal diamond, it has been widely used in the wire drawing industry. Most of the diamond wire drawing dies use PCD wire drawing cores.
- CVD diamond core: CVD diamond, also known as chemical vapor deposition diamond, is a pure diamond deposited on the surface of a solid substrate with carbon-containing gas under high temperature and low pressure conditions. CVD diamond has high hardness, good wear resistance, low friction coefficient and high surface finish. It can be made into wire drawing dies with 0.02-1.0mm aperture for drawing stainless steel wire, tungsten wire, molybdenum wire, copper wire, aluminum wire, etc. Because CVD diamond does not contain any bonding agent, compared with PCD, CVD diamond wire drawing dies show higher wear resistance, corrosion resistance, thermal conductivity and thermal stability. The disadvantage of this product is that its toughness is not as good as PCD, its impact resistance is weak, it is easy to crack, and the technical conditions in the preparation of the wire drawing die are also stricter than PCD.
- Single crystal diamond core: Single crystal diamond has the characteristics of high hardness and good wear resistance. The wire drawn by this type of mold has a high surface finish, but due to the anisotropy in structure, its hardness is also anisotropic. Make the die hole wear uneven, the product is not round, and the resources are scarce, the price is expensive, generally used as a fine wire drawing die or finished wire drawing die with high surface quality requirements. There are two types of single crystal diamond wire drawing cores: natural diamond wire drawing cores and artificial single crystal diamond wire drawing cores. The man-made single crystal diamond wire drawing core is mainly imported. Representative manufacturers include Element Six, Sumitomo of Japan, and Langfang Sipor Company.
How many types of PCD cores are there?
According to different bonding agents, PCD cores can be divided into two types: cobalt-based and silicon-based:
- The cobalt-based PCD core contains a metal bond and has good machinability. It can be processed by electric spark, laser, ultrasonic and other processes. However, the presence of metal cobalt makes diamond easy to graphitize at high temperatures, so this type of mold The core is suitable for processing and use under conditions below 650 degrees Celsius.
- The workability of silicon-based PCD core is relatively poor, but there is no metal bond in the material, so the material can still maintain good thermal stability at 1000 degrees Celsius.